Mike Baird: his ascension to the role was virtually guaranteed when he announced his candidacy on Thursday morning. Photograph: Alan Porritt/AAP

Mike Baird was sworn in as the 44th premier of New South Wales on Thursday evening after he was elected unopposed in a meeting of the parliamentary Liberal party.

The transport minister, Gladys Berejiklian, was elected deputy party leader, also unopposed.

Baird’s ascension to the role was virtually guaranteed when he announced his candidacy on Thursday morning, and any doubts over Berejiklian’s election had dispelled by the time the party met at 3pm.

Her major rivals, the families and communities minister, Pru Goward, and the right faction’s favoured candidate, the energy minister, Anthony Roberts, had both pulled out and thrown their support behind the Baird-Berejiklian unity ticket.

Surrounded by his family, the incoming premier said it was "an honour and a privilege" to lead NSW.

Baird began by paying tribute to his predecessor, Barry O’Farrell, whom he described as “man of integrity” who had turned NSW into a national "pacesetter". On economic growth and jobs, "we were last, we're now first", he said.

He flagged new measures to restrict the influence of lobbyists in the state’s politics, acknowledging the public was “incredibly disappointed and shocked by some of the revelations” arising from the Independent Commission Against Corruption’s (Icac) inquiry into Australian Water Holdings (AWH).

“There is community concerns about fundraising, about donations, about lobbyists … I’ve heard the concerns. We have to take some additional actions, and cabinet will be considering those,” he said.

“Ultimately, what I say to the people of New South Wales is that the Liberal and National government is a government of integrity.”

On the fraught question of selling the state’s electricity infrastructure – considered to be a third rail of NSW politics – Baird said he would stick by his predecessor’s policy: “We weren’t going to do it unless we have a mandate, and that is the position we’re currently in, that’s not changed.”

O’Farrell would continue in his role as member for Ku-ring-gai, Baird said, but would not confirm whether he would contest the 2015 state election. Berejiklian will remain the transport minister.

Baird’s father, Bruce, was a minister in the Howard government. The treasurer, who represents Manly, is considered a centrist but his professed Christianity and conservative social views – he opposes same-sex marriage and adoption by gay couples – have endeared him to the party’s right.

The party’s right faction was reportedly pushing for Roberts to be installed as deputy rather than Berejiklian, considered a warrior of the party’s left. Baird hosed down any talk of a factional unrest, saying the fact he and Berejiklian had been elected unopposed “says volumes to the unity of the party”.

Jostling for the leadership began almost immediately after Barry O’Farrell announced he would be leaving the top job, after a hand-written note emerged on Wednesday suggesting he had received a $3,000 bottle of 1959 Penfolds Grange from the then chief executive of AWH, Nick Di Girolamo.

Under oath on Tuesday, O’Farrell had repeatedly denied ever receiving the wine from the businessman. AWH is the focus of a corruption inquiry investigating attempts to secure a lucrative public-private partnership to build water infrastructure in Sydney’s north-west.

Baird is not entirely free of links to Di Girolamo. In June 2012 he appointed the AWH chief executive to a $34,000-a-year position on the board of the State Water Corporation.

Documents obtained by the state Greens MP John Kaye show that the businessman was ranked poorly by a panel assessing him for a similar role on the board of the Sydney Ports Corporation. The panel said he did “not have relevant industry experience” and had legal experience only in “relatively narrow areas of practice”.

A spokesman for Baird told the ABC that the documents were no proof of a “jobs for the boys” appointment, and that the Liberal fundraiser had been appointed to the board on merit based on the advice of an independent panel.

After his party-room ballot on Thursday, Baird told a news conference Di Girolamo’s appointment, which he signed off, had been approved by the full cabinet. “In hindsight, should that have been done? No,” he said.

He said Icac, which is preparing another investigation involving AWH and the former resources minister Chris Hartcher was “doing its job, pure and simple”.

“If someone has done something wrong, they deserve the book thrown at them,” he said, acknowledging: “Obviously there are inquiries we’d rather weren’t happening.”

Labor warned the new leader would enact “savage cuts” to the state’s health and education system. “Behind the mild-mannered demeanour of Mike Baird is the heart of an ideologue,” the opposition leader, John Robertson, said.

This week a $3,000 bottle of wine toppled New South Wales premier Barry O'Farrell, after he failed to remember receiving a bottle of 1959 Penfolds Grange as a gift from lobbyist Nick Di Girolamo, despite having written a thank-you note. In the light of this, satirists A Rational Fear have made a new advertising campaign for the pricey tipple